Like many comedians of his era, he began in vaudeville and became known for using his violin as a prop. In 1932, he began his radio show, The Jack Benny Program and in 1950, made the successful transition into television winning two Emmy awards.
Benny was famous for his alter-ego personality: never aging beyond 39, a tightwad persona, and inept violin playing (he was actually generous in real life and an exceptional violinist).
Trademarks of his comic routine was when he paused, resting his chin on his hand, and uttered the word "Well!"
or telling his audience in an aside, "Now cut that out!"